Strengths: Switched to these from Brooks T5. Are wearing much better than my T5s - they aren't eva straight on the road so they are more durable in my opinion. Have run over 100 miles in them now, and they still look almost new. Once you get use to how to maximise the effect of the lugs, these shoes are incredibly responsive.
Weaknesses: They are quite pricey, but most other brands seem to be creeping up in price whereas Newtons have stayed the same. As they are more durable, I don't mind paying a bit more. Build up gradually, particularly if planning to wear without socks.
Strengths: Can put in sessions of different lengths. Enough intervals to put in a pyramid. This is why I choose this watch over the cheaper/less complex varieties.
Stores enough data to probably cover a week-long training camp or holiday, which is v useful. Can also choose which ones you erase - ie, you could keep in all your times for a certain loop if you wanted to.
Weaknesses: Plugging in session with differing lengths of recovery can take a while.
Also, when putting in a new session with fewer bits, have to remember to erase all the further intervals, otherwise it will just carry on to them.
Overall: Very pleased. Once you get the hang of it it's a great watch.